Coppered azo dye



Patented Dec. 12, 1950 COPPERED AZO DYE Harry W. Grimmel, Riegelsville, Pa., and Jack F.

Morgan, Phillipsburg, N. J assignors to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application September 20, 1947, Serial No. 775,382

The present invention relates to a coppered monoazo dye which is particularly suitable for dyeing nylon a bright, bluish rubine shade of excellent fastness properties.

The dyeing of nylon has posed a number of problems such as the production thereon of level dyeings which are fast to light and washing. It has been suggested that these problems be solved by employing for the dyeing of nylon metallized azo dyestuffs and in this connection reference is made to U. S. P. 2,374,106 and U. S. Serial No. 391,542, published April 27, 1943.

Inasmuch as nylon is dyed from aqueous baths, a desirable adjunct of the dyes employed is water solubility. It has been found, however, that the groups generally employed to impart solubility in water, the sulfonic acid groups, preclude the proper building up of the dye on the fiber with the result that it is impossible with such dyes to obtain dyeings of a deep shade.

The metallized azo dyes which are most commonly employed for dyeing nylon are those in which the metal forming complex is chromium or cobalt. Such dyes are universally preferred over dyes in which the metallizing agent is copper for the reason that they are more soluble in water and consequently are, in most cases, more readily absorbed by the fibers. It will be noted, for instance, that in application Serial No. 391,542, it is suggested in each example, that the complex azo dye be either of chromium or cobalt.

We have now discovered that the coppered azo dye obtained by coppering the product resulting from diazotizing 2-amino-4-chlorophenol and coupling the resulting diazonium compound with 1-naphthol-5-sulfonamide, yield, when employed to dye nylon, dyeings of a bright bluish rubine shade which are level and which are extremely fast to light and to washing. Our original investigations were carried out with the chromium and cobalt complexes of the aforesaid azo dye since in consonance with the experience of the art, it was thought that these more soluble compleXes would yield the best dyeings. To our surprise, however, we found that the less soluble copper complex yielded dyeings which were far superior to the dyeings obtained with the chromium and cobalt complexes as regards shade. Furthermore, the copper complex was found to have a far greater affinity for nylon than the chromium or cobalt complexes. Our findings in this respect are considered to be unexpected since they are directly contrary to the experience gained by operators in dyeing nylon with metallized azo dyes. The aforesaid copper complex of the azo dye from diazotized 2-amino-4-chlorophenol and 1-naphthol-5-sulfonamide, the process of applying such complexes to nylon fibers, and the dyeings obtained therewith constitute 1 Claim. (Cl. 260-151) the purposes and objects of the present invention.

The diazotization of the 2-amino-4-chlorophenol is carried out with a cold solution of sodium nitrite and hydrochloric acid in the usual manner. Similarly, the coupling follows the usual practice being effected in an alkaline bath at low temperatures of the order of 5-10 C. The coupling reaction is slow and is usually allowed to run overnight. Despite the slowness of the reaction, no difliculties are encountered with it.

O-Nzrrol- The azo dye is metallized with ammoniacal copper sulfate solution at a temperature ranging from room temperature to 60 C. Best results are obtained, however, when the coppering reaction is effected in the neighborhood of 50-60 C.

The reaction leading to the formation of the desired copper complex is illustrated by the following equations, the first, indicating the formation of the azo dye, and the second, the formation of the copper complex:

ONa

OiNHg OH OH S O QNH? Example 14.5 parts of 2-amino-4-chlorophenol are dissolved in '75 parts of water and 20 cc. of concentrated hydrochloric acid. The solution is stirred and cooled to 5-10" C. and then treated with '7 parts of sodium nitrite dissolved in parts of water.

parts of l-naphthol-S-sulfOnamide are dis solved in a solution of 8 parts of sodium hydroxide, 12 parts of sodium carbonate, and 400 parts of Water. This solution is cooled to 5-10 C. with stirring and then treated slowly with the diazo solution prepared as above. The coupling reaction is slow and the reaction mixture is, accordingly, allowed to stir overnight. parts of salt are added and after stirring for 30 minutes, the dye is filtered oil and washed with a small quantity of a 10% salt solution. There is thus obtained parts of a filter cake.

A fine slurry containing no lumps is prepared from the filter cake while using 500 parts of Water. cc. of ammonium hydroxide are added and the slurry stirred for 20 minutes. A solution of 25 parts of copper sulfate in 200 parts of water are added to the slurry and the mixture stirred at 50'5t- C. for 3 to 4 hours. The dye is removed by filtration, Washed with Water, and dried. The material is ground fine and mixed with 4.7 parts ofsodium earbonateto obtain a product for use in dyeing nylon. .;05 g. of the above dyestuff are dissolved heating it to the boiling point with cc. of water cert .ning 2 cc. of a 5% aqueous solution of sodium Nanethyl, l LQleoyltaurin-e: 5 g. or" nylon are entered into the'hath. the heating continued. After 15 minutes, 4 cc. of a 1% acetic acid solution are added. The nylon is removed from the bath after heating for 1 hour, rinsed and soaked by immersing it into 300 cc. of a hot solution containing 5 cc. of a 10% green soap so1ution. After rinsing again, the nylon is dried and conditioned in the usual manner. The nylon is now a deep bluish rubine shade of excellent fastness to light and washing.

.05 g. of the above dyestuil are dissolved by heating it to-the boiling point with 300 cc. of water containing 2 cc. of a 5% aqueous solution of sodium N rnethyl, N-oleoyltaurine and 5 cc. of a 10% solution of glauber salt. 5 g. of nylon are entered into the bath and the heating continuse. The nylon is removed from the bath after heatin for 1 hour, rinsed, dried and conditioned in. the usual manner. The nylon is now dyed a deep bluish ruhine shade of excellent fastness to t and washing. "odifieation-s of the invention will occur to onrs in this field. For instance, in lieu of the n carols-hate added in the coupling reaction, on can employ an equivalent quantity of sodium h Si: arly. the quantity of ammonium h droxide ti. con uering operation may be resay an amount of cc. We, therefore, do not intend to be limited in the patent granted except necessitated by the prior art and appended claim.

We claim:

The coppered azo dye of the following constitution:

SOQNIIQ capable of yielding level dyeings of an attractive bluish rubine shade of excellent iastness properties to light and Washing.

HARRY 'W. GRIMMEL. JACK F. MORGAN.

EF REN JES CITED The following references of record in the of this patent:

OTHER REFERENCES Ser. No. '39'l,54. Mueller et al. (A. P. C), puhllshed Apr. 27,1943. 

